Medical nutrition therapy in type 1 diabetes focuses on integrating the insulin regimen and carbohydrate estimation into the familys lifestyle, conforming to preferred meal routines and food choices. Diets of children with type 1 diabetes are low in fruits, vegetables, and whole grains, and high in saturated fat. Poor diet quality is particularly concerning due to the increased risk of cardiovascular disease associated with type 1 diabetes. However, scant research has examined individual and family determinants of dietary intake, the effectiveness of intervention to improve dietary intake, or the impact of improved diet quality on glycemic control in youth with type 1 diabetes. Intervention studies in other clinical populations demonstrate substantial challenges in promoting healthful eating, and suggest the importance of family-based approaches that enhance motivation, facilitate skills, and assist families in overcoming barriers to healthful eating. CHEF was a randomized controlled trial of a behavioral nutrition intervention targeting improved diet quality in families of youth with type 1 diabetes, for whom diet plays a critical role in disease management. The trial demonstrated the efficacy of a family-based behavioral intervention grounded in health behavior theories to improve overall diet quality and intake of whole plant foods (Nansel et al. 2015, PMID: 25952160). Findings further indicated that diet quality improved most in children demonstrating picky eating behaviors, widely considered as more resistant to improvements in dietary intake (Nansel et al. 2018). Despite concerns that increased attention to diet may increase disordered eating, these behaviors did not increase due to the intervention (Eisenberg et al. 2018, PMID: 29371234). Finally, secondary analyses in the past year suggest that worse diet quality in youth with type 1 diabetes is associated with less favorable cardiometabolic risk factors (Sanjeevi et al., 2018 PMID: 30347780), and that greater adiposity is associated with less favorable bone mineralization (Sanjeevi et al., 2018, PMID: 30114458).